Improvement in hoisting-jacks



L H. SHURCH iLL.

Hoisting-Jacks.

No. 141 91 9. 4 Patented Augusti9fl873. 77

mrneys,

AMPHOTO-LITHUGRAPHIC co. Am(oseomvslc Pn csss) UNITED STATES PATENT OFFICE.

JOHN H. CHURCHILL, OF CROSS RIVER, NEW YORK.

IMPROVEMENT IN HOlSTING-JACKS.

Specification forming part of 'Letters Patent No. 1 1L919, dated August 19, 1873 application filed July 2f3, 1873.

T0 all whom it may concern:

Be it known that I, JOHN H. CHURCHILL, of Cross River, in the county of Westchester and State of New York, have invented a new and Improved Hoistin g-Jack, of which the following is a specification:

In the accompanying drawing, Figure 1 represents a vertical longitudinal section on the line 0 0, Fig. '2; and Fig. 2, a horizontal section on the line a: m, Fig. 1.

' Similar letters of reference indicate c0rre-' spondin g parts.

The object of my invention is to construct a hoisting-jack which is easily operated, effective in action, and readily adjusted to different heights. My invention consists of a bell-crank lever with treadle, which acts by means of an intermediate connecting-rod and weighted link on a sliding rack, guided between a strong frame.

In the drawing, A represents the frame of the jack, consisting of a bottom part, B,'and two parallel uprightposts or pillars, O, of wood, metal, or other suitable material. The bellcrank lever D is pivoted at a to the lower part of pillars O, and provided at its forward projecting arm with a treadle for applying the foot, so as to leave the hands free for adjustingthe sliding rack to the objects to be hoisted. The upward-extending arm of lever D is pivoted at its end to the intermediaterod E, which connects again at its upper end with a weighted link, F, which looks into the teeth of a sliding rack, G. Rack G is guided in longitudinal slot (Lon strong connecting-bolts 1) between the pillars G.

The upper end of rack G is applied in suitable manner to the object, and the rack placed into iposition by raising the lower arm of lever D and sliding rack G'till link F engages it at the required height. Bythen lowering lever D the rack G is raised by the action of y the intermediate rod E and link F. The obdescribed.

JOHN H. CHURCHILL.

Witnesses:

PAUL GOEPEL, ALEX. F. Itonnnrs. 

